1. Field of the Invention
The present invention relates to an electric-component holding head which sucks and holds an electric component by applying negative pressure thereto, and particularly to a filter which is provided in a negative-pressure passage of the head and removes foreign matters present in air supplied through the passage.
2. Discussion of Related Art
There is known an electric-component holding head including a holder member which holds a suction nozzle for sucking and holding an electric component and which is provided by a plurality of members such that the holder member can be disassembled into those members. A filter is provided in a negative-pressure passage which is defined by the plurality of members. The filter removes foreign matters present in the air which passes through the filter when the suction nozzle sucks the electric component. When the filter becomes dirty, it is replaced with a new one, or is cleaned. To this end, the holder member is disassembled into the plurality of members, so that the dirty filter is replaced with a new one, or is cleaned. Then, the plurality of members are assembled again into the holder member, such that the new filter or the cleaned filter is accommodated in the holder member.
However, it is cumbersome to disassemble and re-assemble the holder member each time the filter is replaced with a new one or is cleaned. In addition, a person cannot see, from outside the holding head, to what degree the filter is dirty. For example, in the case where the filter is replaced with a new one at a predetermined period, the filter which is not so dirty and can be used further may be replaced with a new one, which leads to lowering the running cost of the holding head, or the filter which is so dirty and cannot be used any more may be used further uselessly. That is, it is difficult to determine a timing when the filter is replaced with a new one or is cleaned.
The present invention provides an electric-component holding head which has each of the following features. Those features are described, like claims, in respective paragraphs, and those paragraphs are given respective numbers. Any feature that includes another feature shall do so by referring to the number given to the latter feature. However, the following features and the appropriate combinations thereof are just examples to which the technical features, and the combinations thereof, described in the specification are by no means limited. In addition, in the case where one feature recites a plurality of items, it is not essentially required that all of those items be simultaneously employed. That is, it is possible to select and employ only a portion (one, two, . . . , but not all) of those items.
(1) According to a first feature of the present invention, there is provided an electric-component holding head, comprising a holder member including a nozzle-hold portion which holds a suction nozzle, and having a negative-pressure passage through which a negative pressure is supplied to the suction nozzle so that the suction nozzle holds an electric component by applying the negative pressure thereto; a filter which is provided in the negative-pressure passage and removes foreign matters present in an air passing through the filter; the holder member having an outer surface and a filter-insert hole which has an opening in the outer surface and communicates between the outer surface and the negative-pressure passage so that the filter is inserted from outside the holder member via the filter-insert hole into the negative-pressure passage; and a closure member which closes the opening of the filter-insert hole.
The closure member may be attached to the holder member in such a manner that the closure member is pivotable relative to the holder member and accordingly is opened and closed by being pivoted or rotated by an operator, or in a different manner that the closure member is detachable from the holder member. It is preferred that the filter and the closure member be connected to each other as recited in the following feature (2), but it is not essentially required. For example, it is possible to draw out the filter after the closure member is detached or opened.
The nozzle-hold portion may be one which holds a single suction nozzle, or one which holds a plurality of suction nozzles.
Before the filter is removed from the filter-insert hole, the closure member is operated to open the opening of the hole. After the filter is removed through the filter-insert hole, the old filter is replaced with a new one, or is cleaned. After the new or cleaned filter is inserted in the filter-insert hole, the closure member is operated to close the opening of the hole. Thus, the replacing or cleaning of the filter can be done outside the holder member. Therefore, even if the holder member may be one which is obtained by assembling a plurality of constituent members, an operator can easily replace or clean the filter, without needing to disassemble those constituent members. In addition, the holder member may be one which cannot be disassembled, because the replacing or cleaning of the filter can be done outside the holder member. Thus, the present electric-component holding head can employ the holder member which cannot be disassembled and which has the negative-pressure passage in which the filter is provided to remove foreign matters included in the air passing through the passage.
(2) According to a second feature of the present invention that includes the first feature (1), the closure member includes a closure portion which closes the opening of the filter-insert hole, and a filter-hold portion which holds the filter.
The present holding head assures that the attaching of the filter to the holder member and the closing of the opening of the filter-insert hole with the closure member are simultaneously done, and that the detaching of the filter from the holder member and the opening of the filter-insert hole with the closure member are simultaneously done. Thus, the replacing or cleaning of the filter can be easily carried out.
(3) According to a third feature of the present invention that includes the first or second feature (1) or (2), the holder member further includes a first engaging portion, the closure member includes a second engaging portion which engages the first engaging portion of the holder member and thereby fixes the closure member to the holder member, and the head further comprises an elastic member which provides an elastic force with which the first and second engaging portions are kept in engagement with each other.
For example, the second engaging portion of the closure member may be provided by an engaging member which is attached to the closure member such that the engaging member is pivotable relative to the closure member. In this case, the elastic member may be provided by a spring member which biases the engaging member in a direction to keep the engagement of the first engaging portion and the engaging member. According to the sixth feature (6), described later, the easily deformable portions function as not only an attaching device which attaches the second engaging portion to the base portion of the closure member such that the second engaging portion is pivotable, but also as the elastic member.
Since the engagement of the first and second engaging portions is kept with the elastic force, the closure member is prevented from falling off the holder member, while continuing to close the opening of the filter-insert hole.
(4) According to a fourth feature of the present invention that includes the third feature (3), the second engaging portion of the closure member comprises a pair of arms which extend toward the holder member and have respective engaging claws at respective free end portions thereof.
(5) According to a fifth feature of the present invention that includes the fourth feature (4), the closure member further includes at least one operable portion which is operable to move at least one of the pair of arms away from the other of the arms.
It is desirable in view of the ease of operation that the operable portion be provided by the operable levers recited in the following feature (6), but it is not essentially required. For example, the operable portion may be provided by respective portions of the respective free end portions of the two arms that are opposite to the respective engaging claws and are operable with two fingers of an operator to move the two free end portions away from each other. When the filter is detached from the holder member, the operator operates, with his or her fingers, the two operable portions to elastically deform the two arms and thereby disengage the two engaging claws from the first engaging portion. In this case, the arms also function as the elastic member.
(6) According to a sixth feature of the present invention that includes the fifth feature (5), the closure member includes, as the at least one operable portion, a pair of operable levers which extend in a direction opposite to a direction in which the pair of arms extend toward the holder member, and further includes a pair of connection portions each of which connects between a corresponding one of the pair of arms and a corresponding one of the pair of operable levers; a base portion; a pair of easily deformable portions each of which is provided between a corresponding one of the pair of connection portions and the base portion and is more easily elastically deformable than the one connection portion and the base portion, and when the pair of levers are operated such that respective free end portions thereof are moved toward each other, respective free end portions of the pair of arms are moved away from each other because of elastic deformation of the pair of easily deformable portions, so that the respective engaging claws of the pair of arms are disengaged from the first engaging portion.
The respective free end portions of the two arms can be easily moved away from each other, by operation of the two operable levers with a small operating force of an operator. Thus, the filter can be easily detached from the holder member. In this holding head, the easily deformable portions function as not only hinges which connect the arms and the operable levers to the base portion of the closure member such that the arms and the levers are pivotable relative to the base portion, but also as the elastic member which keeps the engagement of the first and second engaging portions.
(7) According to a seventh feature of the present invention that includes any one of the second to sixth features (2) to (6), the filter-hold portion of the closure member includes a shank portion which extends perpendicularly from the closure portion, and a head portion which is formed at a free end of the shank portion, and the shank portion extends through the filter and the head portion prevents the filter from falling off the shank portion.
The filter may be permanently fixed to the filter-hold portion, or may be detachably attached to the same. In the former case, when the filter is replaced with a new one, the closure member is also replaced with a new one; and when the filter is cleaned, the closure member may also be cleaned. In the latter case, only the filter may be replaced with a new one, or be cleaned.
(8) According to an eighth feature of the present invention that includes the first feature (1), the holding head further comprises an attaching device which attaches the closure member to the holder member such that the closure member is pivotable relative to the holder member; and a closure-state keeping device which keeps a state in which the closure member closes the opening of the filter-insert hole.
When the filter is replaced with a new one, or is cleaned, the closure member is pivoted in a state in which the closure-state keeping device is not operated to keep the closure state. After the filter is replaced or cleaned, the closure member is operated to close the opening of the filter-insert hole and the closure-state keeping device is operated to keep the closure state.
(9) According to a ninth feature of the present invention that includes the eighth feature (8), the holding head further comprises a filter-hold member which is separate from the closure member and holds the filter.
The eighth feature (8) allows such a manner that the filter-hold member and the closure member are integrally formed with each other according to the second feature (2). In this case, when the closure member is pivoted, the filter is inserted into, or drawn out of, the filter-insert hole. The attaching device may be one which allows the closure member to be detached from the holder member when the filter is replaced with a new one or is cleaned. Otherwise, the filter may be one which is detachable from the filter-hold portion. However, in many cases, it is more convenient to employ the filter-hold member which is separate from the closure member according to this feature.
When the filter is replaced or cleaned, the closure member is pivoted to open the opening of the filter-insert hole and take out the filter with the filter-hold member. The filter may be permanently fixed to the filter-hold member, or may be detachably attached to the same. When the filter is replaced with a new one, the filter-hold member may, or may not, be replaced with a new one. After the filter is replaced or cleaned, the filter held by the filter-hold member is inserted into the filter-insert hole and the closure member is operated to close the opening of the filter-insert hole.
(10) According to a tenth feature of the present invention that includes the eighth or ninth feature (8) or (9), the closure-state keeping device includes a first engaging portion which is provided by a free end portion of the closure member, and a second engaging portion which is provided by a portion of the holder member and engages the first engaging portion.
(11) According to an eleventh feature of the present invention that includes any one of the first to tenth features (1) to (10), the closure member is formed of a substantially transparent material so that in a state in which the closure member closes the opening of the filter-insert hole, the filter is visible from outside the holder member through the closure member.
The transparency of the material used to form the closure member may be at a degree which assures that the closure member enables an operator to see and judge whether the filter is dirty or not, or to what degree the filter is dirty. Thus, the material may be substantially transparent. In addition, it is preferred that the material be colorless and transparent. However, the material may be colored and transparent.
The closure member is entirely formed of the transparent material, starting with an inner surface thereof facing the filter-insert hole and ending with an outer surface thereof opposite to the inner surface, so that an operator can externally see the filter through the closure member. Thus, the operator can replace the filter with a new one, or clean the filter, if he or she sees the filter from outside the holder member and finds that the filter is so dirty as to be replaced with a new one or be cleaned. In this case, the operator can replace or clean the filter at an appropriate timing that is not too early or too late. If the timing when the degree of dirtiness of the filter is inspected by the operator after the commencement of use of the filter is pre-set at a time which is somewhat earlier than expected, he or she can surely find a dirty filter without delay of time. If the operator sees the filter and finds that the filter is not so dirty as to be replaced or cleaned, he or she can postpone the timing of inspection of the filter, without replacing or cleaning the filter. Thus, the filter can be replaced or cleaned at high cost performance. In addition, since the dirty filter is replaced or cleaned at the earliest possible timing and is no longer used, the foreign matters included in the negative-pressure air supplied through the negative-pressure passage are effectively removed by the filter.
(12) According to a twelfth feature of the present invention, there is provide an electric-component holding head, comprising a holder member including a nozzle-hold portion which holds a suction nozzle, and having a negative-pressure passage through which a negative pressure is supplied to the suction nozzle so that the suction nozzle holds an electric component by applying the negative pressure thereto; a filter which is provided in the negative-pressure passage and removes foreign matters present in an air passing through the filter; and at least a portion of the holder member is formed of a substantially transparent material so that the filter is visible from outside the holder member.
The transparency of the material used to form the portion of the holder member may be at a degree which assures that the portion of the holder member enables an operator to see and judge whether the filter is dirty or not, or to what degree the filter is dirty. Thus, the material may be substantially transparent. In addition, it is preferred that the material be colorless and transparent. However, the material may be colored and transparent.
The above-indicated eleventh feature (11) is one embodiment according to this feature (12). However, the present feature (12) may otherwise be embodied. For example, an electric-component holding head which does not employ a closure member may employ a holder member at least a portion of which is formed of a substantially transparent material. In the latter case, if a portion of the holder member that surrounds the filter is substantially entirely formed of the transparent material, an operator can easily inspect whether the filter is dirty. Otherwise, it is possible to form a through-hole in a portion of a wall surrounding the filter and permanently fill the through-hole with a substantially transparent material.